Run test workflows on python 3.10

Signed-off-by: Christian König <ckoenig@posteo.de>

.github/workflows/test.yml

@@ -51,10 +51,10 @@ jobs:
       name: Checkout repository
       uses: actions/checkout@v3.0.2
     -
-      name: Set up Python 3.8
+      name: Set up Python 3.10
       uses: actions/setup-python@v4.2.0
       with:
-        python-version: 3.8
+        python-version: '3.10'
     -
       name: Install dependencies
       run: pip install -r test/requirements.txt